Toyota, Honda, General Motors, Nissan, Ford, and Stellantis all improved their supplier relationship scores in the 2026 Plante Moran Working Relations Index (WRI), marking the first time in the study’s 26-year history that every major North American automaker advanced simultaneously despite tariff pressures, EV cost disputes, and ongoing logistics volatility.

The 2026 results reflected a shift in how suppliers evaluate automakers during a period defined by supply chain disruption, electrification costs, and geopolitical uncertainty. According to the study, cited by Automotive Logistics, suppliers increasingly rewarded OEMs for communication, accessibility, and collaboration, even when automakers were unable to fully resolve pricing or cost-recovery disputes.

Toyota retained the top position in the WRI with 409 points, becoming the first automaker to surpass the 400-point threshold since 2007. Honda ranked second with 360 points after improving by 13 points and entering the “good to very good” category. General Motors gained eight points to reach a record 318, while Nissan increased six points to 255. Ford posted the largest year-over-year improvement, rising 32 points to 223, while Stellantis remained in last place despite gaining 22 points to reach 163.

Dr. Angela Johnson, principal and supplier relations analytics leader, Plante Moran, said the results surprised analysts given the current industry environment.

“It really could have gone the other direction; we had to check three times when we saw everyone came out positive,” Johnson told Automotive Logistics.

The study collected more than 10,000 supplier comments, compared with approximately 2,800 in the previous edition. Suppliers highlighted actions such as taking meetings, returning calls, listening to concerns, and maintaining transparency during periods of uncertainty.

Johnson said suppliers reported “less frustration” and “less finger-pointing” as automakers demonstrated a greater willingness to communicate proactively and address problems earlier in the process.

One of the study’s main findings was that communication and accessibility now carry more weight in supplier evaluations than in previous years. Suppliers indicated they increasingly value efforts to maintain open dialogue, particularly during negotiations related to tariffs and electric vehicle cost-recovery programs.

Tariffs and electrification expenses remain major sources of tension across North America’s automotive sector. Johnson noted that supplier experiences varied significantly within the same automaker. Some suppliers described OEM support as strong, while others considered responses insufficient, reflecting the complexity of cost allocation tied to EV programs and trade measures.

Toyota and Honda received the highest evaluations for fairness and transparency in tariff-related negotiations, reinforcing their long-standing supplier management models. General Motors was recognized for responding quickly and remaining receptive to supplier concerns, although some suppliers cited increased operational demands linked to the company’s resilience initiatives.

Ford and Stellantis also received recognition for becoming more proactive and accessible. Johnson attributed Ford’s improvement partly to efforts led by Liz Door, Ford’s chief supply chain officer, as well as broader supplier engagement initiatives, including the implementation of a two-way supplier scorecard designed to improve transparency.

The 2026 study also included an analysis of the 50 largest suppliers in North America. The results showed that Japanese automakers continued to outperform Detroit manufacturers in trust, communication, and profitability opportunities. Toyota, Honda, and Nissan all scored above their overall averages among major suppliers, while GM, Ford, and Stellantis ranked below their broader averages.

Johnson said these differences remain rooted in organizational history and supplier culture. “Detroit’s traditional relationships with suppliers were historically more adversarial, while Japanese manufacturers built collaboration models based on trust and mutual respect,” she said, adding that “organizational memory” in the automotive industry can take decades to change.

Plante Moran identified six key behaviors that define stronger OEM-supplier relationships: commercial fairness, consistency, clear expectations, communication, continuity, and collaboration. The study concluded that suppliers increasingly prioritize collaborative behavior over transactional relationships during what industry analysts describe as a “permacrisis” environment.

Johnson summarized the challenge facing automakers and suppliers across North America: “Working together is the best way to confront the challenges of the permacrisis, innovate, and grow.”